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排序方式: 共有1378条查询结果,搜索用时 9 毫秒
21.
JP Gagliardi RE Nettles DE McCarty LL Sanders GR Corey DJ Sexton 《Canadian Metallurgical Quarterly》1998,26(5):1165-1168
The effect of age on the presentation and outcome of infective endocarditis (IE) is unclear. Many of the available data are based on analyses of mixed populations of patients including intravenous drug users or those with prosthetic valve endocarditis or native valve IE. We used the Duke criteria to compare the characteristics of 44 episodes of definite native valve IE in elderly patients (> 64 years old) with the characteristics of 64 similarly defined episodes of native valve IE in younger, nonintravenous-drug-using adult patients (> 29 years and < 60 years old). Our data suggest that the clinical presentation, characteristics, and outcome of native valve IE are similar for elderly patients and younger adult patients, although elderly patients were hospitalized an average of 12 days longer. Although we found that the occurrence of renal failure and cerebral embolism during an episode of IE was associated with higher rates of death (odds ratios, 4.8 and 4.0, respectively), age was not a significant contributor to mortality. 相似文献
22.
MJ Telford JW Martin BJ Rock LL Turik JE Hairfield 《Canadian Metallurgical Quarterly》1994,19(3):25-9, 33
Small local chapter groups can present quality cost effective regional seminars. Key components are dedication of members, teamwork, and a sense of direction. The following guidelines and information can provide a framework for planning and coordinating a seminar. 相似文献
23.
24.
SS Cohen DJ Mason LS Arsenie SM Sargese D Needham 《Canadian Metallurgical Quarterly》1998,23(6):48, 54, 57-460 passim
Decades of practice and research suggest that nurse practitioners (NPs) provide cost-effective and high-quality care. Managed care's emphasis on prevention and cost savings led some policy makers to view NPs as a way to meet the need for primary care providers. However, access to and utilization of NPs has increasingly been controlled by managed care organizations (MCOs) through their selection of providers for primary care panels. This study employed qualitative methodology to examine NPs' experiences with MCOs. Three focus groups, comprising 27 NPs in New York and Connecticut, revealed NPs' mixed reactions to managed care and a range of sentiments regarding NPs' efforts to be listed as primary care providers. The results reflected NPs' concerns about their perceived "invisibility," as well as their sense of "invincibility" in the ways in which NPs are responding to the barriers posed by MCOs. They identified barriers to, as well as ways to facilitate, being listed by MCOs, and described the importance of NPs working individually and collectively in negotiating with MCOs. 相似文献
25.
LL Bachrach 《Canadian Metallurgical Quarterly》1996,47(10):1071-1078
OBJECTIVES: This analytical review is intended to update the author's earlier writings on the position of the state mental hospital within the spectrum of services for long-term mental patients and to provide perspective for the next generation of service planners. METHODS: Findings and commentary are organized around four major questions. First, what is the prevailing view of state mental hospitals today, and how does it compare with the view that existed in the first half of this century? Second, what individuals tend to be served in state mental hospitals today? Third, what has been the fate of mentally ill persons who are no longer served in state mental hospitals? Fourth, what is an appropriate role for the state mental hospital in today's uncertain and rapidly changing systems of care? Source material consists of periodical articles suggested in MEDLINE searches, plus newspaper reports, recent books on mental health service systems, and a variety of writings found in the "fugitive" literature generally not indexed in traditional archives. RESULTS AND CONCLUSIONS: Individual state mental hospitals vary in the composition of their resident populations, the content of their services, and the overall quality of their care. Although they have been superseded by community-based service structures in some places, they continue in general, as the result of their multifunctionality, to occupy a critical place in systems of care. Renewed efforts to integrate them as full partners within those systems must be undertaken. 相似文献
26.
D. J. Needham 《Journal of Engineering Mathematics》1984,18(4):259-271
Summary This paper examines the small-amplitude free-surface motions on a homogeneously fluidized bed for which the density ratio % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeqyWdi3aaS% baaSqaaiaadAgaaeqaaOGaai4laiabeg8aYnaaBaaaleaacaWGZbaa% beaakiablQMi9iaaigdaaaa!3E84!\[\rho _f /\rho _s \ll 1\], where f is the fluid density and s is the solid density. It is shown that to leading order in % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeqyWdi3aaS% baaSqaaiaadAgaaeqaaOGaai4laiabeg8aYnaaBaaaleaacaWGZbaa% beaaaaa!3C65!\[\rho _f /\rho _s \], the surface motions are independent of the dynamics of the bed varying only with the dimensions of the bed and the conditions at uniform fluidization. Also, at leading order, it is found that provided the fluidization remains homogeneous there is a direct analogy between waves on the free surface of a fluidized bed and waves on the free surface of an inviscid liquid (when surface tension is neglected). 相似文献
27.
Summary The evolution of a small-amplitude localized voidage disturbance through a two-dimensional fluidized bed is considered. A solution of the full initial-value problem reveals that the stability condition for the uniform state is found to be in agreement with that given by Needham and Merkin [1] for narrow beds. Further, it is shown that for a given flow rate for which the uniform state is unstable, more and more cross-channel modes become instable with increasing bed width, in accordance with the observations of Didwania and Homsy [3]. Finally a solution is obtained forF 1, whereF is the Froude number. The resulting Fourier series is summed numerically, which enables the evolution of the initial disturbance to be followed by plotting contours of constant voidage with increasing time. This shows that in narrow beds the motion is primarily one-dimensional, confirming the supposition of [1], with cross-stream variations becoming more dominant as the bed width increases. 相似文献
28.
With the ever-increasing use of pharmaceuticals and the relatively high risk of developing drug allergies, particularly for patients in hospitals and for ambulatory patients with a history of drug allergy, the need to develop in vitro assays for drug allergy is great. In the early 1970's a mast cell technique was developed for diagnosis of drug allergies. A PRIST inhibition assay has also recently been developed to detect IgE antibodies to drug allergens. This test has also been referred to as the Total IgE Inhibition Test by Specific Drug Allergen, and is a variant of the in vitro RAST Test. In vitro mast cell and IgE inhibition tests are applied for identification of drug and chemical allergens and for their cautious clinical trial to prevent future drug and chemical reactions. Over the last eight years, over 1,300 patients were examined utilizing the mast cell technique. Over 100 drugs were tested, with penicillin, barbiturates, "caine" derivatives and sulfonamides most frequently employed. Of 270 patients with well-defined drug reactions, 190 (70 per cent) gave a positive response to the mast cell test. Eighty-five per cent of sera tested with Type I reactions gave a mast cell response. Of these, a group of 30 patients was studied with PRIST inhibition as well. Procedures for comparative testing of necessary drugs and/or chemicals in cases of high anaphylaxis risk of reaction in the clinical setting, hospital or office are included in the study as well as individual case reports. Mast cell assay coupled with IgE inhibition has been successfully used to diagnose drug and chemical allergic reactions. The incidence of positivity is high when the offending drug causes a Type I allergic reaction. The cases reported indicate that both the Mast Cell and the PRIST inhibition assays are useful for diagnosing and setting the clinical treatment and clinical course of the patient. The mast cell assay would be potentially employed for patient use in hospitals where the incidence of drug allergy is highest and for occupational health in the chemical industry. The greatest potential would be in outpatient care applied to patients with multiple drug allergies in the selection of safe drugs (test negative by both methods, and other clinical studies) for future drug usage. 相似文献
29.
RH Margolis PL Schachern LL Hunter C Sutherland 《Canadian Metallurgical Quarterly》1995,34(5):232-247
Multifrequency tympanometry (MFT), using probe frequencies ranging from 226-2,000 Hz, was performed on normal chinchillas to obtain normative data against which to compare results from animals with middle ear pathology. A series of validating experiments was conducted to determine the effects of anatomical alterations of the middle ear on MFT. These included artificially extending the ear canal, opening the bulla, injecting saline into the middle ear, and disrupting the ossicular chain. The results indicate that MFT characteristics of chinchilla ears are qualitatively similar to those observed in normal humans and patients with middle ear disease, and MFT provides information that is not available from the 226-Hz tympanogram. 相似文献
30.
C.A. Sidwell P.A.S. Needham J.D. Harrington 《New Review of Information Networking》2013,18(1):121-135
Technical reports are an important and unique source of engineering information. This has been recognised in the US where federal technical reports are freely available via the Internet. UK reports are hard to identify, locate and obtain. Within the context of new initiatives promoting cross‐sectoral partnership and collaboration, the Research Support Libraries Programme (RSLP) and British Library Co‐operation and Partnership Programme (BLCCP) have funded the MAGiC project. MAGiC aims to provide the UK engineering community with a greater awareness of, and access to, key collections of technical reports by: mapping UK report collections; developing a methodology for prioritising digitisation of reports; providing an entry point to search and browse widely distributed resources; developing a core electronic archive of engineering report literature; evaluating the feasibility of creating a commercial service based on the supply of electronic documents. An exposition of work in progress is given with a projection of how the demonstrator service will operate. A call for help with the project in locating report collections within academia, industry, and government, and contact details, are given. 相似文献